Pbocess fob coating metal



UNITED, STATES PATENT OFFICE.

BENJAMIN I. ALLEN, OF GREAT NECK STATION, NEW YORK.

No Drawing.

To all whom it may concern:

Be it known that I, BENJAMIN P. ALLEN, a citizen of the United States, residing at Great Neck Station, in the county of Nassan and State of New York, have invented certain new and useful Improvements in a Process for Coating Metal, of which the following is a specification.

This invention has relation to processes for coating metal, and has for an object to provide a process and composition of matter for imparting to iron or other metallic castings, metallic articles or the like, a coat-' mg ored to resemble brass.

A still further object of the invention is to provide a process and composition of matter for the above named object, of a nature to permit the use of electricity as an agent in causing the deposit of material upon the article. 4

My process resembles electroplating to some extent, in that the article to be coated 7 together with an electrode are connected to .a source of current and then immersed ina suitable bath whereby the articles take on a coat of material of the desired thickness whereby the articles when dried present, to all intents and purposes the appearance of brass.

The plating or coating bath of my inven tion is composed of the following materials and preferably in the proportions named:

Water 80 c. c. Acetic acid 10 c. c. Lead chromate PbGrO grains.

A suitable quantity of this solution is placed in a receptacle and heated. While the bath is hot, the'articles to be coated aresuspended from a suitable support and the support connected to the positive pole of a battery, generator, or other suitable source of current supply capable of generating a current of two'amperes, under an electrometive force of approximately three-quarters of a volt. The articles thus constitute theanode. The negative pole of the source of current is then connected to an iron plate which is dipped intothe bath thereby con-i stitutingthe cathode. Attention is called to the fact that this arrangement is the reverse of that in the ordinary electro plating process wherein the articles form the oathode of the bath.

While the bath is heated, the articles" are Specification of Letters Patent. Application filed February 19, 1917. Serial No. 149,550.

of material whereby the'articleis 001- PROCESS FOR COATING METAL.

Patented July 17', 1917.

dipped therein thereby completing the circult through the bath and after moving the articles about they are slowly removed and permitted to dry. The first dip results in the deposition of coloring matter in isolatedareas, or patches, 'it is therefore necessary to reimmerse the articles until a uniuired.

f0r m coating thereon has been a ThIS may require two or three dips efore the desired result is obtained. However,

after the articles are withdrawn from the bath and before reimmersing they must be thoroughly dried. I have found that the constant agitation of the bath to retain the insoluble lead chromate in solution insures a more rapid deposition of coloring matter upon the articles, and I have furthermore discovered that if the solution is brought to the boiling point to bring about rapid convection, the chromat c will be suit ably retained in suspension. If desired however, suitable mechanical means may be provided for agitating the solution. Relative to the proportions of the ingredients named above, the same may be varled,

althoughan excess of lead chromate should not be permitted to be present as the depositionnpon the articles will be of a more or less granular character. To obviate this, an "additional quantity of acetic acid may be added to the bath.

Furthermore, while it has been my ex perience that an electric current of the strength above named, accompanied with a small electromotive force is productive of good results, it may not be necessary to em steel, or other metallic articles may have impartedthereto a color strongly resembling the yellow color of. brass. In this manner, ron and steel castings may be tents and purposes.

While I have set forth my invention with made to resemble brass castings to all in;

setting forth the nature some particularity,

and the proportions in of the ingredients,

which theya'ie combined, as well as other details of operations entering into the process, nevertheless, I realize that in practice other ingredients may be substitutedfor those named or the proportions varied, I therefore reserve the right and. privilege of substituting equivalent ingredients for those or othnamed, rearranging the proportions, erwise varying the steps of my process to perform the desired and contem l'ated ref sults, within the spirit of the lnvention,

and the scope of the appended claims.

Having thus described my invention, what I claim as new and: desire to secure Letters Patent is:-

ing metal, wh' ch consists in first immersing the article in a bath which includes in its composltion, water, lead chromate, and ace- 1. The herein described process for coat tic acid, and finally introducing a current acetic acid ten parts, and lead chromate two and six-tenths parts. v p

4. A bath for coating metal, which includes in its compos1t1on,water eighty cubic centimeters, acetic acid ten 'cuhic centimeters, and lead chromate forty grains In testimony whereof I afiix my slgnature in presence of vtwo witnesses.

BENJAMIN P. ALLEN.

Witnesses:

DANIEL S. WooLLEY, James K. RYAN. 

